System-size dependence of the charged-particle pseudorapidity density at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV for pp, p-Pb, and Pb-Pb collisions

Abstract

We present the first systematic comparison of the charged-particle pseudorapidity densities for three widely different collision systems, pp, p-Pb, and Pb-Pb, at the top energy of the Large Hadron Collider ($\sqrt{s_{\mathrm{NN}}}=5.02$ TeV) measured over a wide pseudorapidity range ($-3.5<\eta <5$), the widest possible among the four experiments at that facility. The systematic uncertainties are minimised since the measurements are recorded by the same experimental apparatus (ALICE). The distributions for p-Pb and Pb-Pb collisions are determined as a function of the centrality of the collisions, while results from pp collisions are reported for inelastic events with at least one charged particle at midrapidity. The charged-particle pseudorapidity densities are, under simple and robust assumptions, transformed to charged-particle rapidity densities. This allows for the calculation and the presentation of the evolution of the width of the rapidity distributions and of a lower bound on the Bjorken energy density, as a function of the number of participants in all three collision systems. We find a decreasing width of the particle production, and roughly a smooth ten fold increase in the energy density, as the system size grows, which is consistent with a gradually higher dense phase of matter.

arXiv comment18 pages, 6 captioned figures, authors from page 13, published version, figures at http://alice-publications.web.cern.ch/node/7846

References in corpus (22)

• Experimental and Theoretical Challenges in the Search for the Quark Gluon Plasma: The STAR Collaboration's Critical Assessment of the Evidence from RHIC Collisions
• Formation of dense partonic matter in relativistic nucleus-nucleus collisions at RHIC: Experimental evaluation by the PHENIX collaboration
• Quark Gluon Plasma an Color Glass Condensate at RHIC? The perspective from the BRAHMS experiment
• The PHOBOS Perspective on Discoveries at RHIC
• EPOS LHC : test of collective hadronization with LHC data
• Performance of the ALICE Experiment at the CERN LHC
• Charged-particle multiplicity density at mid-rapidity in central Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 2.76 TeV
• Phobos results on charged particle multiplicity and pseudorapidity distributions in Au+Au, Cu+Cu, d+Au, and p+p collisions at ultra-relativistic energies
• Centrality dependence of the pseudorapidity density distribution for charged particles in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 2.76 TeV
• Improved version of the PHOBOS Glauber Monte Carlo
• Charged-particle multiplicities in proton-proton collisions at $\sqrt{s}$ = 0.9 to 8 TeV
• Glauber modeling of high-energy nuclear collisions at sub-nucleon level
• Further developments of a multi-phase transport model for relativistic nuclear collisions
• Centrality dependence of the pseudorapidity density distribution for charged particles in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV
• Charged-particle production as a function of multiplicity and transverse spherocity in pp collisions at $\sqrt{s}$ = 5.02 and 13 TeV
• Measurement of the centrality dependence of the charged-particle pseudorapidity distribution in proton--lead collisions at $\sqrt{s_{{}_{\mathrm{NN}}}}=5.02$ TeV with the ATLAS detector
• Nuclear stopping and rapidity loss in Au+Au collisions at sqrt{s_{NN}}=62.4 GeV
• 3D Jet Tomography of Twisted Strongly Coupled Quark Gluon Plasmas
• Centrality evolution of the charged-particle pseudorapidity density over a broad pseudorapidity range in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 2.76 TeV
• Measurement of transverse energy at midrapidity in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=2.76$ TeV
• Pseudorapidity distributions of charged particles as a function of mid and forward rapidity mutiplicities in pp collisions at $\sqrt{s}$ = 5.02, 7 and 13 TeV
• Recent lattice QCD results and phase diagram of strongly interacting matter

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